spazmatron Posted May 12, 2006 Report Share Posted May 12, 2006 I just received my first two core kits (core-R4) from Smash. The boards look great!I would like to link the two cores for 128 buttons and 16 encoders.I've got a few quick questions before I start soldering.1. How do I have power indicator leds? 10 or 20 for illumination. Not responding to MIDI, I just want them to come on when the power is on.2. Specifically what should I use for a power supply? (2 cores + 2 of Smash's lcds + 20 leds) Do I need 2 seperate power supplys or just one. I have read the J1 description on Smash's site, but I don't know that much about electricity, so I want to be sure.3. How do I add a Power switch? (ON/OFF)4. If I'm using the MIDIbox link, do I leave the optocoupler off of one of the cores?5. Will MIDIO128 + MIDIbox64E work for what I want?Thanks for any help!! You guys are awesome!!-let me know if this should have been under a different catagory. Quote Link to comment Share on other sites More sharing options...
Rowan Posted May 12, 2006 Report Share Posted May 12, 2006 Brendon, is that you ;Dsorry i don't have time to anserw your questions...........running late for work.Rowan Quote Link to comment Share on other sites More sharing options...
dengel Posted May 12, 2006 Report Share Posted May 12, 2006 I'll answer a few of these:1) You could easily hook the LEDs up to a spare power pin on the core, if you have one. MAKE SURE YOU USE THE RIGHT RESISTOR with your LED, otherwise the LED can burn out almost immediately. different color LEDs have different resistor and power requirements; read the spec sheets for the part to find out what you need to know.2) Use a 9v DC power supply, and the cores will regulate it down to 5v as needed. Make sure that you have enough power for everything. A core with LCD and pots/buttons can draw around 500ma - overpower you PSU, and frankly I recommend a wall-wart for ease of construction. I would shoot for a 9v/1.5-2.0 amp power supply, which will give you all the power you'll need without over-volting and wasting electricity and creating a heat dissipation issue.You only need one power supply. There are pins on the core that give power to a second connected core.3) Easiest way for a power switch is either:a) A quick-connect panel mount plug on the back of your unit, same size as your wall-wart connector.b) if you want, just install a panel mount rocker switch in line with your PS, and permanently wire your wart wires to a 2-pin connector for the power supply pins on the core.4) No Idea.5) Yes. Think of it this way - the M64e can use 128 DIN pins (4 DINx4's). Buttons take one pin (the other is ground) and encoders take 2 pins.So, with 16 encoders subtract 32 pins, leaving you with 96 buttons left. In addition, MB64e can handle (via AINs) an amazing additional 64 POTS too (MB64E maps these pots to slots 64-128 of the encoders; this is a newer version of the e, but it's in the changelog)!Imagine what a commercial midi controller with 128 rotary inputs and 96 buttons would cost... Thanks, TK! Quote Link to comment Share on other sites More sharing options...
smashtv Posted May 12, 2006 Report Share Posted May 12, 2006 1) You could easily hook the LEDs up to a spare power pin on the core, if you have one. MAKE SURE YOU USE THE RIGHT RESISTOR with your LED, otherwise the LED can burn out almost immediately. different color LEDs have different resistor and power requirements; read the spec sheets for the part to find out what you need to know.Whoa horsey!Average led=20 ma.20 of these is an extra 400ma load, that's almost half of your available 5v current on the core....run more leds, modules, LCD backlight etc and there will be problems.Don lets get your first box done before we start sending the new guys down the "whoops I let out the magic smoke" path please..... ;)BestSmash Quote Link to comment Share on other sites More sharing options...
moebius Posted May 12, 2006 Report Share Posted May 12, 2006 Yeahh..1. As Smash already pointed out.. Leds used for lighting aren't "critical" in such sense that they would need regulated voltage. That would just put necessary stress on regulator on the core. Those are best connected to power after the power switch with proper current limiting resistors for wallwart voltage. You can find "led resistor calculator" easily online. With ultra-bright leds, it's usually better to use (and test) much higher resistances than needed nominal maximum current for led.4. Yes. You leave optocoupler out of the core where You connect the first core directly.Moebius Quote Link to comment Share on other sites More sharing options...
dengel Posted May 12, 2006 Report Share Posted May 12, 2006 Average led=20 ma.20 of these is an extra 400ma load, that's almost half of your available 5v current on the core....run more leds, modules, LCD backlight etc and there will be problems.Whoa, missed the "10-20" part in his post. Yeah, thatsa lotta "illumination". I'd use a seperate power supply for that many too. Quote Link to comment Share on other sites More sharing options...
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